Work feeding device



Sept. 26, 1950 R. G. LE TOURNEAU 2,523,836

WORK FEEDING DEVICE Original Filed Feb. 20, 1942 2 Sheets-Sheet 1INVENTOR (/12 R. GLeTour-neau m2; M AHZ Patented Sept. 26, 1950 WORKFEEBING DEVICE Robert G. Le Tourneau, Peoria, 111., assignor to R. G. LeTourneau, Inc., Stockton, Califl, a corporation of California Originalapplication February 20, 1942, Serial No. 431,729. Divided and thisapplication April 22, 1946, Serial No. 664,081

Claims.

The subject matter of this application is a division of originalapplication, Serial No. 431,729, filed February 26, 1942, now Patent No.2,401,833, dated June 11, 1946.

An object of the instant invention is to provide a work feedingmechanism for case hardening apparatus for like machine elements, whichincludes mechanism to continuously advance a row of such machineelements at a predetermined speed; the elements as they advance eachpassing first through a heating zone and subsequently through aquenching or cooling zone.

A further object of the invention is to embody in the apparatus novelmeans to regulate or vary the rate of feed of the machine elementsthrough the heating and quenching zones, whereby to control the depth ofsurface hardening of said elements.

An additional object of the invention is to pro vide a work feedingmechanism for case hardening apparatus which is operative not only tocontinuously feed like machine elements through heating and quenchingzones, but also is operative to simultaneously rotate the elements asthey passthrough said zones, whereby to assure even and rapid heatingand cooling of the elements. l

A further object of the invention is to produce a practical device andone which will be exceedingly effective for the purpose for which it isdesigned.

These objects I accomplish by means of such structure and relativearrangement of parts as will fully appear by a perusal of the followingspecification and claims.

In the drawings: Figure 1 is an enlarged elevation of the improved casehardening apparatus including the improved lineal work feedingapparatus. 1

Figure 2 is an enlarged fragmentary sectional elevation of the bearingassembly and the lineal feed mechanism.

Figure 3 is an enlarged fragmentary section on line 33 of Fig. l; 7

Referring now more particularly to the characters of reference on thedrawings, the apparatus comprises a fixed base i having an upstandingrelatively short tubular post 2 secured thereto in rigid relation; thebase 1 having a circular opening 3 matching with the bore of the postand of slightly greater diameter. A horizontal turn" table 4 is disposedabove the base i intermediate the ends of post 2, the latter projectingcentrally through the turntable. The turntable is rotat ably mounted inconnection with post 2 and held against downward axial displacement bymeans of a suitable bearing assembly indicated generally at 5 which isenclosed within a sleeve-like housing 6. A cap 1 is fixed concentricallyon the top of the turntable and encloses the upper end of post 2 and theadjacent portion of the enclosed bearing assembly, the top of cap 1being fiat and forming a horizontal platform 8. A circular opening 9 insuch platform matches the bore of post 2, and is of a diameter at leastthat'of the bore of said post.

A plurality of upstanding guide bars It are mounted symmetrically and incircumferentially spaced relation on platform 8 and about opening 9,such guide bars ll] being rectangular in cross section and disposed sothat the inner faces I l of opposed bars are parallel; the spacing ofopposed bars being substantially the diameter of the cylindrical pins H!which the apparatus is designed to receive and treat. Adjacent theirupper ends the guide bars H) are secured together by means of asurrounding connecting ring it.

In vertically spaced relation above the guide bars iii, which of coursemove with the turntable, there is mounted another assembly of relativelyshort stationary guide bars I i which are arranged in the same relationto each other as the guide bars it, and about the same vertical axis.The guide bars M are supported adjacent their upper ends by a bracketwhich overhangs the apparatus from a fixed frame it, and are connectedadjacent their lower ends by a surrounding ring 16a.

A flame ring and quenching assembly indicated generally at ll in Fig. lis disposed horizontally intermediate adjacent ends of guide bars '50and Hi and is disposed concentric with the then continue downwardlybetween and are guided by bars ill, finally discharging out of thebottom of the apparatus through tubular post 2. In order to regulate thelineal speed of the pins through the apparatus the following lineal feedcontrol mechanism is employed:

A plurality of V-pulleys l8 are arranged in vertical banks on oppositesides of the stack of pins; the pulleys of each bank being supportedbetween transversely spaced plates l9 hich upstand from platform 8. Thepulleys are mounted for rotation about horizontal axes and are disposedwith their peripheries in opposed relation; adjacent portions of thesepulleys projecting centrally from between guide bars Ill toward butbeing slightly clear of the stack of pins. Each vertical bank includesan endless V-belt 29 which passes about the endmost pulleys and whoseinner reach 2| rides the intermediate pulleys; said in ner reach beingvertical and on the outside frictionally engaging the pins 1 2 of thevertical stack in holding relation. An automatic belt tightener,indicated generally at 22, cooperates with the other reach of each beltoutwardly of the corresponding bank of pulleys. It will be seen thatwith rotation of pulleys H3 in a direction to move the inner reaches 2|in a downward direction, the stack of pins l2 which are frictionallyengaged and normally supported by said reaches will be lowered and pinsdischarged-from the stack at a corresponding lineal speed.

The vertical banks of pulleys of the lineal feed mechanism are driven inthe following manner:

The shafts of the lowermost pulleys of each bank are fitted with drivepulleys 23 exteriorly of one plate l9. The pulleys are driven inopposite directions by a reverse drive belt 24 which passes about adrive pulley 25 of a variable speed reduction gear unit 26 mounted onturntable 4 to one side of the platform 8; there being a suitable belttightener 21 cooperating with belt 24. The speed reduction unit 25includes a pulley 28 driven-by an endless belt 29 from an electric motor30 mounted on the turntable on the opposite side of cap I, the motor 30deriving its current from an independent power circuit 3| through themedium of means such as a collector ring assembly on the turntableindicated at 32.

In order to assure proper frictional engagement of the reaches 2| ofbelts 20 with the downwardly moving pins 12 of the vertical stack, thevertical banks of pulleys are mounted for adjustment on platform 8in aninner direction by any suitable means such as that shown at 33.

In the present disclosure this adjustment means comprises flanges 33a onthe lower ends of the plates 19, which flanges are provided with slots33b. Bolts 33c are fixed to the platform 8 and project through the slots33b, and are provided with locking nuts 33d. Upon loosening these nutsthe plates may be adjusted in either direction and the nuts may then betightened to hold them in such adjusted position.

The vertical banks of pulleys terminate at their upper ends aconsiderable distance below the flame and quenching ring assembly H.

In order to rotate the turntable and consequently the lineal feedmechanism and pins l2 engaged thereby, said turntable is formed as apulley engaged by a drive belt 34 which extends to a stationary variablespeed electric motor (not shown).

In operation, the stack of pins l2 to be casehardened-passes downwardlythrough the apparatus at a speed of approximately seven to eight inchesper minute, while rotating at approximately 150 R. P. M.; the heatingand subsequent quenching of the pins as they are rotated undercontrolled lineal speed assuring that the desired case hardening isaccomplished. By varying the speed of travel, the effective depth of thecaseharde'ning can be governed. Pins (SAE 1045 steel) treated in thisoperation are hardened to a depth of approximately .045 to .050effective and depth, providing a very hard thin surface and leaving avery tough core.

The feed mechanism described is operable to control the desired speed oftravel while continuously rotating the stack of pins [2 as they passthrough the heating and quenching zone I! as is essential to the properheat treatment thereof.

From the foregoing description it will be readily seen that I haveproduced such a method and apparatus as substantially fulfills theobjects of the invention as set forth herein.

While this specification sets forth in detail the present and preferredconstruction of the apparatus and method of operation, still in practicesuch deviations from such detail may be resorted to as do not form adeparture from the spirit of the invention, as defined by the appendedclaims.

Having thus described my invention, what I cl'aimas new and useful anddesire to secure by Letters Patent is:

l. A work feeding device comprising a fixed base, an upstandingrelatively short tubular post on said base, the base having an openingin register with the interior of the post, a platform disposed above thebase and having an orifice in register with the interior of the post,such platform being rotatably mounted on the post, a group of verticallydisposed guide bars fixed to the platform in spaced relation about theorifice therein, vertically supporting plates on the platform disposeddiametrally of said orifice, banks of pulleys on each of said plates andprojecting into spaces between adjacent ones of said guide bars, endlessbelts disposed about each bank of pulleys and having their inner runsfacing the through spaces between said guide bars, and power mechanismoperative to drive the pulleys and belts at a predetermined speed.

2. A device as in claim 1, including means for rotating the platform,such latter means including a turntable journaled about the post, theplatform being mounted on the turntable, and power means operative toimpart rotation to the turntable.

3. A structure as in claim 2 in which the pulleys and belt drivingmechanism are mounted on the turntable.

4. A device as in claim 1, including means for adjusting the pulleysupporting plates radially with respect to the vertical axis of theplatform.

5. In a device for the downward feeding of cylindrical work piecesdisposed with their axes vertical, diametrally opposed pairs of fixedvertical guide bars engaging about the pieces with a running fit, anddriven belts having vertical downwardly moving runs frictionallyengaging the pieces along diametrally opposed portions thereof exposedbetween adjacent guide bars.

ROBERT Gr. LE TOURNEAU.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

